The diagnosis and treatment of ductal carcinoma in situ (DCIS; the earliest stage of breast cancer) triggers a cascade of physical and psychological effects that may endanger a woman's long-term health. Less than 3% of women with DCIS will die from breast cancer within 15 years of their diagnosis. But due to their diagnosis and treatment, women with DCIS typically experience elevated weight gain, high rates of antidepressant use, and declines in domains of health-related quality of life including physical function and vitality. These impacts may have adverse effects on a variety of other health outcomes which likely represent a greater threat to a woman's health than breast cancer. The specific objectives of this proposal are 1) to examine the burden of non-breast cancer disease among DCIS survivors; 2) to evaluate socioeconomic status as a predictor of adverse changes in health-related behaviors after a DCIS diagnosis; 3) to determine the relative importance of health-related behaviors in influencing overall mortality after DCIS; and 4) to determine the association between health-related behaviors and health-related quality of life among women with DCIS. To accomplish these aims we will perform two retrospective cohort studies using data from the National Cancer Institute's Surveillance, Epidemiology and End Results (SEER) Program and the Wisconsin In Situ Cohort (WISC) study. We will examine mortality among over 125,000 women diagnosed with DCIS over the past 35 years in the 18 SEER registry sites geographically dispersed around the country. We will use health-related behavior, quality of life, and outcomes data collected in the WISC study during up to 15 years of active follow-up of 1,959 DCIS cases diagnosed between 1995 and 2006 in the state of Wisconsin. New data collection via patient surveys and data linkages with Medicare, the US Census, and the National Death Index is proposed. The prevalence of DCIS is projected to surpass 1 million by the year 2016. This proposal will provide evidence that clinicians and patients can use to improve DCIS health outcomes and will provide researchers with a foundation for the development of effective behavioral interventions that can improve the long-term health of women with DCIS.